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May 25, 2021

What’s new for Microsoft Edge at Microsoft Build 2021

Welcome back to Microsoft Build! Wherever this finds you, we hope that you’re safe and healthy.

Since last Build, the Microsoft Edge platform continues to empower developers with the latest tools ready for today’s evolving web landscape. In the State of the Platform video below, Program Managers Scott Low and Zoher Ghadyali detail what’s new and what’s improved on the Microsoft Edge web platform.

So, what’s new for developers since Build last year?

  • WebView2 is generally available and is now included with WinUI 3: Over the last year, WebView2 has become generally available and is supported across app frameworks like Win32 C/C++, WPF/WinForms, and now WinUI 3! WebView2 is Microsoft’s embedded web control, built on top of Microsoft Edge (Chromium). WebView2 is decoupled from the Windows operating system and lets you combine the ease and agility of developing for the web with the power of building a native desktop application. Whether for web, hybrid, or native apps, WebView2 treats these supported app frameworks as first-class citizens so you can bring the best of the web to your apps.
  • Morgan Stanley embraces WebView2 to help future-proof their technology: Since we started working on WebView2, Morgan Stanley has been a close partner in giving feedback, helping us to ensure WebView2 is meeting business needs. By adopting WebView2, Morgan Stanley has given their employees the power of native app experiences combined with the latest web app technology. Using WebView2 keeps that web technology evergreen with updates and security, which was something that their previous Chromium containers solution couldn’t do.
  • WebView2 Runtime is more broadly available to power WebView2 apps: Whether you plan to develop WebView2 apps in a fixed or evergreen state, you’ll need the WebView2 runtime to support them. To support your WebView2 apps, we’re making the WebView2 Runtime available in more places—for example, through dedicated installers and future Windows releases—so that it’s ready for use by you and your users.

And, what’s improved?

  • 5,300 Chromium commits accepted: Making the web better for everyone is essential to our mission for Microsoft Edge. Since launch, we’ve had over 5,300 commits accepted back into the Chromium project so that many of the improvements we’ve worked on for Microsoft Edge can be experienced by others using a Chromium-based browser.
  • Edge Origins Trials continue, and expand: Announced last year and embraced by the developer community, our Edge Origins Trials program continues to offer new experiences for developers to test and preview—join hundreds of other developers in an Origin Trial by registering through
  • PWAs join the Microsoft Store: Progressive Web Apps (“PWAs”) built on the Microsoft Edge platform are now available in the Microsoft Store, and yours can be too! Broaden the reach of your PWA in 3 easy steps:
  1. Create an app reservation in the Windows Partner Center
  2. Package your PWA for Windows with
  3. Submit the package to the Microsoft Store for approval

Microsoft Edge takes performance to the next level

You care about the developer tools, but we also know that you want great experiences when people use your website or application—and browser performance is essential to that. Since last Build, we’ve added new features to boost browser performance and because of this Microsoft Edge will be the best performing browser on Windows 10 when Microsoft Edge version 91 releases later this week!

So, why can we say this? It’s simple: Startup boost and sleeping tabs.

First, Startup boost launches Microsoft Edge more quickly by running a set of core Microsoft Edge processes in the background, all without adding additional resources when Microsoft Edge browser windows are open. Turning on your computer and getting online with Microsoft Edge just became that much faster.

Animation showing Sleeping Tabs in Microsoft Edge

Second, the new sleeping tabs feature gives Microsoft Edge a performance boost when using multiple browser tabs simultaneously. It helps optimize the performance of your Microsoft Edge browser by freeing up system resources from unused tabs. This month, sleeping tabs is further improved and with up to 82% memory savings based upon internal data collected on our preview builds. It does so by immediately putting ads to sleep when you put tabs in the background for instant resource savings. Sleeping tabs also now has additional improvements to save system resources on Windows.

The future of Internet Explorer is in Microsoft Edge

Finally, you may have heard our recent announcement that the future of Internet Explorer on Windows 10 is in Microsoft Edge and that the Internet Explorer 11 (“IE11”) desktop application will be retired on June 15, 2022 for specific versions Windows 10. We know that catering to specific browsers are top pain points for you, so this news means that you will be able to focus more of your efforts on modern web experiences. But we didn’t leave your customers and users behind either. With Internet Explorer mode in Microsoft Edge, consumers and organizations will be able to use IE-based sites and apps alongside modern ones in Microsoft Edge—this is what we call the dual engine advantage in Microsoft Edge.

Timeline showing the retirement date for IE11 on June 15th, 2022

With this retirement date set, we recommend you develop a plan to end support for IE11 for your websites and apps, and to stage a process to transition users from Internet Explorer over time and with easy pathways forward. When you’re ready, we can help you with this. When end users land on a website that is no longer supporting their go-to browser, it can be disruptive and jarring. We can help, with a guided transition process and a one-click option to bring over important user data like passwords and favorites. Learn more in the Moving users from Internet Explorer to Microsoft Edge article. Transitions are hard but can be made easier.

For further details about this announcement, read our blog and check out our FAQ.

Enjoy Edge at Build

We hope you enjoy Microsoft Build this year and feel energized by all the new developer innovations! Don’t miss the following sessions to learn more about Microsoft Edge and WebView2:

And to see all the developer resources related to Microsoft Edge, we’ve conveniently compiled everything for you here:

Have a great Build!